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        <td class="header">&nbsp; Horizontal/Vertical Motion<br>
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<h3>Horizontal/Vertical Motion Operator</h3>
<p class="MsoNormal">Given two (collocated) ascending and descending interferograms, this operator computes the horizontal
    (East-West) and vertical motion. It is assumed that the motion occurred in these two directions only.

<h4>Input<br>
</h4>
<p class="MsoNormal">
        The input to this operator should be a product that has resulted from collocating two terrain-corrected interferograms.
        Such a collocated product can be created by following these steps:
        <ul>
            <li>
                Create an interferogram for an ascending orbit.
            </li>
            <li>
                Create an interferogram for a descending orbit (note: the dates of each InSAR pair should be selected and
                sorted such that they correspond with the ascending interferogram).
            </li>
            <li>
                Multilook (or apply Goldstein filter to) both interferograms and perform phase unwrapping.
            </li>
            <li>
                Apply the <b>Range Doppler Terrain Correction</b> operator to both interferograms, so that they are geocoded. Make sure you
                select the "Incidence angle from ellipsoid" option.
            </li>
            <li>
                Use the <b>Collocate</b> operator to align the terrain-corrected interferograms.
            </li>
        </ul>

<h4>Output<br>
</h4>
<p class="MsoNormal">
    The output of this operator is a product with the following bands:
        <ul>
            <li>
            horizontalMotion: East-West deformation in millimeters.
            </li>
            <li>
            verticalMotion: vertical deformation in millimeters.
            </li>
        </ul>
    <br>

<h4>Parameters<br>
</h4>
<p class="MsoNormal">The X and Y positions of a reference pixel should be selected.

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